It’s been a great week of planting weather regarding warmer days and soil temps! There were even a couple beautiful calm days! Thanks to those of you who filled out my quick survey last week. The results of 36 respondents showed in 2023: 17 planted corn first, 8 planted soybean first, 5 planted corn and soybean at the same time, and 6 hadn’t planted yet. So, the survey did informally show that 13 of the 36 people who responded plant soybeans earlier or at the same time as corn. The CropWatch article I was mentioning was released last Friday if you’re curious regarding the data behind some of the key points I stated last week: https://go.unl.edu/gqt3.
For this week’s article, will share answers to a number of questions I’ve received the past few weeks.
Pesticide cards: This has been my daily top question as producers are needing certification to purchase and pick up restricted use pesticides. For those who attended ANY in-person or online Extension training, you must pay the $25 fee to NDA that comes as a bill in the form of a postcard in order to receive your license. If you didn’t receive a postcard or misplaced it, the quickest way to pay the $25 fee via credit card is to call NDA at (402) 471-2351. This number gets you to the switchboard. Say that you need to pay your $25 fee to get your license and they will connect you with the NDA plant protection office. You will need to say your name, address, birth date, when you took the training and where, and may need to confirm your applicator number (unless you are new). You will then get your card and be listed in the ‘certified’ database that anyone can look up.
For those calling who still needing training, your only option is the online training and please read the directions mentioned once you register at this site: https://go.unl.edu/4tzw. There’s a test out option where you can take the test before going through any modules. If you pass, you’re done and NDA will send you your postcard bill. If you don’t pass, it will then let you take the modules and retest as many times as needed. Please call the UNL pesticide office with questions: 800-627-7216.
Drought Assistance Webinar: If you missed it, here’s the USDA Drought Assistance Webinar recording for Nebraska: https://go.unl.edu/ba8f.
- Fertilizers for Vegetables in Home Gardens (most garden soil tests I’ve seen in this part of State show minimal need for fertilizer!): https://extensionpublications.unl.edu/assets/pdf/g945.pdf
- Simplifying Soil Test Interpretations for Turf (Here’s a great NebGuide resource that’s very visual and shares Nebraska recommendations): https://turf.unl.edu/NebGuides/g2265.pdf.
- With soil temps over 50F for several days and this week’s temps continuing to be warm, for those who’ve asked, it’s time to get crabgrass preventer on lawns.
For those who planted new or overseeded Kentucky bluegrass or tall fescue grass this spring, I’m getting questions about what to do to prevent crabgrass. There is a product from Scotts called “Scotts Turf Builder Triple Action Built for Seeding” (blue bag) that’s supposed to be safe. It contains fertilizer and herbicide claiming to prevent crabgrass and dandelions for up to 6 weeks. Not an endorsement, just sharing an option. I hadn’t chosen to use it in past years because I knew the lawn would look interesting with white patches in the green, but decided to try it this year so I could see how well it worked for future questions. It contains mesotrione (a herbicide that is a pigment inhibitor, so it will turn your newly emerged weeds white). It gets reactivated with water. My lawn doesn’t have an irrigation system and gets watered sporadically, so I’m unsure if it would look better or worse with irrigation. So far, the dandelions are turning white and my lawn is thickening up. A person may need another crabgrass preventer product after 6 weeks, depending on how the lawn thickens, to catch the late flush that often appears.
Hope you had a blessed Easter weekend! Reminder that soil temperatures can be viewed at: https://cropwatch.unl.edu/soiltemperature.
Hay and Forage Resources: Resources for buying/selling hay, corn residue, and other forages can be found at the following:
- Nebraska Hay & Forage Hotline: https://nda.nebraska.gov/promotion/hay/index.html
- Nebraska Hay Exchange: http://www.hayexchange.com/ne.php
- Crop Residue Exchange: https://cropresidueexchange.unl.edu/
Fire Damage to Crop Residue: With the dry conditions and various fires that have occurred, have received questions regarding the nutrient value in the residue and/or soil impacts. When residue is burned, most nitrogen and sulfur in the residue are lost; however, the phosphorus and potassium are retained in the ash (as long as they don’t blow away).
In spite of this, short-term nutrient loss from the residue is none to minimal. Research from the University of Wisconsin looked at the need to replace nitrogen to the succeeding corn crop when soybean residue was either removed or not removed. They found no difference in nitrogen impacts to the corn crop regardless if the residue was removed; this suggests there is no need to replace the nitrogen in burnt soybean residue. Research from USDA-ARS in Nebraska, when looking at corn residue removal prior to corn planting, also suggested no need to replace the nitrogen lost from the residue. They found increased mineralization due to the change in C:N ratio when residue was removed. Previous research compiled in this resource from South Dakota State shared the same sentiments: https://openprairie.sdstate.edu/cgi/viewcontent.cgi?article=1365&context=extension_extra. The SDSU resource is also helpful when walking through a dollar value of other loss considerations.
Regarding longer-term nutrient loss, a UNL NebGuide shares for every 40 bu/ac of corn or sorghum, approximately one ton of residue is produced. Each ton of corn and sorghum residue contains approximately 17 lb N, 4 lb P2O5, 37 lb K, and 3 lb S. For every 30 bu/ac of soybean residue, approximately one ton of residue is produced with 17 lb N, 3 lb P2O5, 13 lb K, and 2 lb S for each ton of residue produced.
Perhaps the greatest losses to consider are organic matter, soil loss, and soil moisture. Regarding organic matter, the soil holds the greatest portion of this. One year of residue is minimal, attributed with the potential of increasing organic matter 0.03-0.06%, depending on tillage type, crop, etc. Soil erosion due to wind/water can result in organic matter loss and loss of more productive soil. This is hard to quantify. Perhaps the more important factor is the soil moisture losses in no-till, non-irrigated fields, particularly in a dry year such as this. Paul Hay, Extension Educator emeritus, years ago shared with me several documented situations where yield losses due to moisture loss were estimated. Corn planted into burned no-till, non-irrigated soybean stubble ranged from 15-28 bu/ac yield loss in two situations. There was 0-3 bu/ac yield loss associated with soybean planted into burned, no-till, non-irrigated corn residue in two situations. Use of soil moisture probes can give an indication of soil moisture differences between burned and non-burned areas of fields or between fields. Direct yield comparisons between fields are difficult to make due to planting dates, hybrids/varieties, agronomic practices, etc., but important to still collect and assess.
Crabgrass Preventer timing: Crabgrass germinates when soil temperatures are maintained at 55F for 5-7 consecutive days. You can watch the CropWatch soil temperature maps at the link listed above. Or, use a meat thermometer (that you dedicate to only taking soil temperature!) for your own lawn situation at a 2-4” depth. Typically, towards the end of April/beginning of May is a good time for the first application, but it will vary by year. So far, this timing is holding true for 2022. When crabgrass preventer is applied too early, it can move out of the zone where the crabgrass seed is germinating. Would also recommend that you consider splitting your crabgrass herbicide application. Apply half of the highest labeled rate when soil temps warm and the other half 6-8 weeks later. Often there’s a flush of crabgrass later in the season and splitting the application can help with that It’s helpful for the products to be watered in within 24 hours for best results.
Household Hazardous Waste Clean-Up will be held at four times and locations for residents of Polk, York, Butler, and Seward counties. These clean-ups are funded by Environmental Trust grants with Four Corners Health Dept. and various sponsoring organizations overseeing the collection at the locations.
The collections will occur:
- Polk Co.: Saturday, April 17 from 8:00 a.m. – 11:00 a.m., Polk County Fairgrounds, Osceola
- York Co.: Saturday, April 17 from 1:00pm – 4:00pm at the York Landfill, 1214 Road 15
- Seward Co.: Saturday, April 24 from 8:00am – 12:00 p.m. at City of Seward Wastewater Plant Parking Lot – 1040 S Columbia
- Butler Co.: Saturday, April 24 from 1:30pm – 4:30pm at Butler County Fairgrounds, 62 L Street, David City – North Entrance
On the specific date and time, residents of that county are welcome to bring their residential household hazardous waste in boxes. Paint in one box and other materials in a separate box. If you are not sure what something is, keep it away from other materials.
Acceptable Materials (quantities of more than 5 gallons cannot be accepted): Acids, Antifreeze, Banned Materials (chlordane, DDT, etc), Cyanide, Fertilizers (yard chemicals), Flammables, Gasoline and Oil (in small quantities), Lead Acid Batteries, Mercury and Mercury-Related Materials, All Paint and Paint-Related Materials (stains, varnish, etc), Poisons, Pesticides, Florescent Bulbs (please do not tape together)
Non-Acceptable Materials: Empty/Dried Out Paint Cans (these can go directly into your regular trash), Tires, Farm Chemicals, Electronics, Medical Sharps, Recyclables.
IN SEWARD COUNTY ONLY: They’re also additional collections at the same date/time: Scrap Metal & Appliances $5 per appliance or load of metal. Electronics Recycling: $10 – all LCD monitors; $20 – CRT (glass tube) monitors or tv’s up to 25″; $30 – TV’s 27″ and up; $40 – Large wooden projection TV’s.
Soil Temperature information for planting and applying pre-emergence herbicides can be found at: https://cropwatch.unl.edu/soiltemperature.
Crabgrass Preventer timing: Crabgrass germinates when soil temperatures are maintained at 55F for 5-7 consecutive days. We’re getting closer to this. You can watch the CropWatch soil temperature maps at the link listed above. You can also use a meat thermometer (that you dedicate to only taking soil temperature!) for your own lawn situation at a 2-4” depth. Typically, towards the end of April/beginning of May is a good time for the first application, but it will vary by year. When they’re applied too early, they can move out of the zone where the crabgrass seed is germinating. Would also recommend that you consider splitting your crabgrass herbicide application. Apply half of the highest labeled rate when soil temps warm and the other half 6-8 weeks later. Often there’s a flush of crabgrass later in the season and splitting the application can help with that. It’s helpful for the products to be watered in within 24 hours for best results.
Pastures and annual grass control: Have looked at several smaller pastures (often grazed by horses & hayed) that have issues with foxtail. Foxtail tends to emerge when soil temps are sustained around 60F, so using a pre-emergent herbicide such as Prowl H20® can help in addition to grazing management. There’s a good article in this week’s CropWatch regarding annual grass weed control for alfalfa and pastures at: https://go.unl.edu/nzmy.
Planting Considerations: In an article last year at this link https://jenreesources.com/2020/04/12/jenrees-4-12-20/, I shared about planting considerations. I don’t have anything new to add to this, so you can check that out if you’re interested. Next week will share results of a soybean and corn germination/emergence experiment I’ve been working on since Mar. 10.
Well, winter seems to be sticking around. My thoughts and prayers have been with those of you calving with the difficult conditions this year.
I provided an update regarding soil moisture status in non-irrigated fields both in this week’s UNL CropWatch at cropwatch.unl.edu and my blog at jenreesources.com. We’ll see what happens with moisture in the next few weeks and I’ll post updates to my blog.
Very few have tried planting in this part of the State that I know of. Grateful for all of you who keep me updated on what’s going on through your questions and comments! In this week’s UNL CropWatch, Dr. Roger Elmore took the lead on an article addressing corn planting. The message is to ideally wait till soil temperatures reach 50F with weather conditions allowing soil temperatures to remain at 50F or higher for the next 48 hours. We’ve observed when seed was planted and a cold snap with cold rains was received within 48 hours, some problems with seed germination and emergence. Hybrids vary in cold tolerance and seed companies are a great resource for that information as to which hybrids could be planted first in colder soils. Soil temperature information can be found at the UNL CropWatch site at: https://cropwatch.unl.edu/cropwatchsoiltemperature. We’d also recommend you take the soil temperature in the field before you plant and can do so by using a meat thermometer.
Last year I remember receiving questions from April 21-24 regarding planting corn and soybeans with an anticipated cold snap later that week. At that time, I was recommending growers switch to soybeans. The reason? Soybeans imbibe (uptake) water more quickly than corn seeds and while we hear 48 hours to be on the safe side, the critical period is more like 24 hours. Also, several years of both small plot and on-farm research in Nebraska has shown the primary way to increase soybean yields is to plant early. Dr. Jim Specht’s research showed soybeans produced a new node every 3.75 days once V1 occurs. The nodes are where pods and seed occur. Our on-farm research planting date studies also showed regardless if the spring was cold/wet or warm/dry, the early planted soybean always out-yielded the later planted with a total average across trials of 3 bu/ac. The data ranged from 1-10 bu/ac. We never planted early without using an insecticide/fungicide seed treatment to protect that seed, so we recommend you add that if you do plant early.
Our recommendation would be to plant the last week of April or as close to May 1 as conditions allow. We’ve also seen good results after April 20 in years if the soil temperatures were around 50F with good weather conditions at least 24-48 hours after planting to maintain that soil temp. It’s important to know your level of risk, though. Crop Insurance planting date for replant considerations is April 25 and there may also be replant options from your seed suppliers. We never replanted any of our studies and I have only observed frost on soybean cotyledons one year where growers planted early with soybeans coming out of it. We had the largest number of acres I’ve seen planted by April 24 last year with thankfully no issues and they were able to take advantage of a high-yielding bean year. Perhaps this is something you wish to try for yourself this year? Consider planting some passes of soybeans early and come back with some passes three weeks later. You can use this Soybean Planting Date Protocol if you’re interested in trying this for yourself. Please let me know if you’re interested in this!
Depending on the number of acres you have, some growers are now planting soybeans first. Others are planting corn and soybeans at the same time by either running two of their own planters/drills or custom hiring someone to plant soybeans for them. This also spreads risk and can help with harvest. Regarding maturities, a study conducted at UNL East Campus compared a 2.1 vs. 3.0 maturity group variety at 10 day intervals beginning April 23 through June 19. Yield was highest for early planted soybean and a yield penalty of 1/8 to 1/4 bu/ac per day of delay in planting for MG2.1 and MG3.0 varieties, respectively was found. The study also indicated that yield of the MG3.0 variety was higher relative to the MG2.1 variety in early plantings (late April and early-mid May), but the opposite (greater yield in MG2.1 versus MG3.0 variety) was found for late plantings (late-May and June). In our part of the State, we’ve observed really high yields from strong genetics in the MG2.4-2.5 varieties when planted early; so I have a hard time automatically recommending later MG varieties without more data. Thus, I would love to work with anyone interested in planting early comparing a high yielding MG2.4-2.5 vs. a high yielding MG3.0-3.5 to obtain more data. Here’s a Soybean Maturity Group Comparison with Early Planting protocol to consider and please let me know if you’re interested in this!
Wheat: My colleague, Dr. Nathan Mueller in Dodge County, has taken the lead on
sharing wheat information for Eastern Nebraska. He’s put together an excellent resource on his blog at http://croptechcafe.org/winterwheat/. Every Friday he’s sharing an update called “What’s up this Wheat“. He also started an Eastern NE wheat listserv and his website explains how to subscribe to it. Grateful for his effort in this as we both have goals of increasing crop diversity in the areas we serve and there are many benefits to wheat in rotation!
Crabgrass prevention in Lawns: Just a quick note that while our Extension lawn calendars promote applying crabgrass preventer in mid-April, our horticulture experts say to wait till soil temperatures are 55F on a seven day average and we are currently far from that! Check out https://cropwatch.unl.edu/cropwatchsoiltemperature for soil temp info.